ASSIGNING TABLE PRIVILEGES

Using pgAdmin III I created the following Group Roles:
* admins
* clients

I also created the following Login Roles:
* admin
* client

I added the admin login role to the admins group role and the client login
role to the clients group role.

admin
admins

clients
client

Now I want to assign privileges in a table so I got its Properties and went
to the Privileges tab. In the Privileges section (about in the middle of the
Properties window) there is a dropdownlist where I am suppose to select a
role but only the "public" appears, I do not see the ones I added. I
disconnected and connected from the database and the new roles I added do
not appear either. What am I missing?

Respectfully,
Jorge Maldonado